Multi-chamber rotary pump



March 1964 G. E. RYDBERG ETAL 3,

MULTI-CHAMBER ROTARY PUMP Filed June '7, 1957 12 Sheets-Sheet 1 George Emil Rydberg Albert/(l. Jacobs Perez? Char/es Jacobs INVENTORS.

March 17, 1964 RYDBERG L 3,125,031

MULTI-CHAMBER ROTARY PUMP Filed June '7, 1957 12 Sheets-Sheet 2 George E mi/ Rydberg Albert J. Jacobs Peter Char/es do .9

INVENT March 17, 1964 G. E. RYDBERG ETAL 3,125,031

MULTI-CHAMBER ROTARY PUMP Filed June 7, 1957 12 Sheets-Sheet 5 lIIIIIIII George Emil Rydberg Albert J. Jacobs Peter Char/es Jacobs INVENTORS.

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Filed June '7, 1957 March 17, 1964 G. E. RYDBERG ETAL 3,125,031

MULTI-CHAMBER ROTARY PUMP l2 Sheets-Sheet 7 Filed June 7, 1957 Fig. 2/

George Emil Rydberg Albert J. Jacobs Peter Char/es Jacobs INVENTORS.

March 17, 1964 Filed June 7, 1957 Fig.2?

G. E. RYDBERG ETAL MULTI-CHAMBER ROTARY PUMP 12 Sheets-Sheet 8 George Emil Rydberg Albert J Jacabs Peter Char/es Jacobs INVENTORS.

March 17, 1964 Filed June '7, 1957 Fig.28

G. E. RYDBERG ETAL MULTI-CHAMBER ROTARY PUMP l2 Sheets-Sheet 9 George Emi/ Rydberg Albert J. Jacobs Peter Char/es Jacobs IN VEN TORS.

March 17, 1964 e. E. RYDBERG ETAL 3,125,031

eorge Emil Rydberg BY MM 29m en J. Jacobs Peter Char/es Jacobs INVENTORS.

G. E. RYDBERG ETAL MULTI-CHAMBER ROTARY PUMP March 17, 1964 12 Sheets-Sheet 11 Filed June '7, 1957 mi/ Rydberg .Jacobs Peter Char/es Jacobs INVENTORS.

BY M Attorneys F. J Wt w WM 6 A March 17, 1964 G. E. RYDBERG ETAL MULTI-CHAMBER ROTARY PUMP 12 Sheets-Sheet 12 Filed June 7, 1957 Fig. 33

5 N ha a am 0 T d S N V J E SW C 6 /a PM h eNC g f f m m 6M8 GAP United States Patent 3,125,031 MULTl-CHAMBER ROTARY P George Emil Rydberg and Albert J. Jacobs, Calgary, Al-

berta, and Peter C. Jacobs, Edmonton, Alberta, Canada; Mary Caroline Denise Cote, executrix of said George E. Rydberg, deceased Filed June 7, 1957, Ser. No. 664,321 14 Claims. (Cl. 103131) This invention comprises a novel and useful multichamber rotary pump and more generally pertains to fluid pressure pumps, motors, engines and such similar devices as are characterized by cyclically expanding and contracting working chambers. The term pump, as used hereinafter, is intended to refer generically to all such devices.

The primary purpose of this invention is to provide a fluid pressure pump or the like of the expansible chamber type in which the volume of the working chamber shall comprise a very large proportion of the total volume of the device.

A further object of the invention is to provide a pump or similar device of the expansible chamber type in which the Working stroke shall continue throughout a very large proportion of the rotation of the working element of the device.

Another object of the invention is to provide a pump or similar device in accordance with the preceding objects in which fluid pressure pulsations produced in or applied to a rotary element of the apparatus shall be reduced to a minimum; and whereby a much more even application of power to or from the rotary element shall be secured.

A still further important object of the invention is to provide a pump or similar device of the expansible chamber type which shall have an extremely small volume and over-all size in comparison with the effective volume of the working chamber of the device, and shall be readily reversible in its rotation.

Still another object is to provide a device of the character above set forth, wherein opposed pairs of working chambers shall be combined to dampen any pulsations in the fluid flow therethrough and whereby thrusts imposed upon the mechanism shall be balanced.

An additional object is to provide a device in accordance with the preceding objects wherein a simple rotary piston element shall operate in a pair of working chambers; wherein the number of moving parts shall be reduced to a minimum; and wherein power is transmitted between a fluid under pressure and a continuously rotating shaft through a continuously rotating element to thereby eliminate the varying inertia effects of reciprocating elements.

Yet another object is to provide an apparatus in conformity with the aforementioned objects wherein a greatly simplified fluid inlet and outlet control means is provided for the working chambers.

Another purpose is to provide in an apparatus of the type enumerated above means for effectively removing any fluids leaking past the sealing means between the rotor, stator and core.

Another object is to provide a fluid pump or motor in which the advantages of positive displacement of the fluid by the rotor are realized with the advantages of a continuous uniform rotation of the rotor.

A further object is to provide a fluid pump having an annular working chamber with a continuously revolvable rotary piston therein together with a partition or blade across the chamber having operative engagement with the piston.

A still further object in accordance with the immediice ately preceding object is to provide a pivotal connection between the blade and the piston.

A very important object of the invention is to provide a pump having an annular working chamber with inner and outer walls and a ring piston therein having tangency with both said walls together with means for imparting a limited circular movement to the piston whereby to cause the points of tangency to rotate continuously and uniformly about the working chamber.

An additional object is to provide a pump in compliance with the immediately preceding object wherein a relatively stationary partition or blade extends across the annular chamber, on both sides of the ring piston to constitute the abutment or cylinder head of the working chamber.

Yet another object is to provide a device of the charac ter set forth above wherein any desired combination of working chambers may be effectively combined into a unitary apparatus, and in such a manner as to eliminate the necessity of counterbalancing off-center oscillatory masses.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURES 1-6 illustrate a preferred embodiment having opposed working units in accordance with this invention, in which:

FIGURE 1 is an elevational view of a fluid pressure, actuated pump or similar device of the expansible chamber type, parts being broken away and shown in section;

FIGURE 1A is a detail view taken in vertical section substantially upon the plane of the section line 1A1A of FIGURE 1 and showing a sealing means employed between the blade and rotor;

FIGURE 2 is a vertical transverse sectional view taken substantially upon the plane indicated by the section line 22 of FIGURE 1 and showing details of the rotor member disposed in the stator and surrounding a stationary core forming a part of the stator to provide a pair of concentric working chambers;

FIGURE 3 is a horizontal longitudinal sectional view taken substantially upon the plane indicated by the section line 3-3 of FIGURE 1 but with the rotor being rotated to a position from that shown in FIGURE 2;

FIGURE 4 is a detail view in vertical section on section line 44 of FIGURE 1 illustrating a gear pump for removing leakage fluid from the device;

FIGURE 5 is a perspective view of the rotary piston comprising the sole rotor element of each unit of this embodiment of the invention;

FIGURE 6 is a perspective view of a blade constituting a partition or end wall of the two concentric working chambers of this embodiment;

FIGURES 7-14 are sequential diagrammatic views illustrating successive stages in the rotation of the rotary piston in this embodiment of the invention and showing more clearly the relative disposition of the two working chambers during such rotation, these views being applicable to each unit in all of the embodiments disclosed in this application;

FIGURES 15-19 are diagrammatic sequential sectional views illustrating successive stages in one complete cycle of operation of the embodiment of pump disclosed in FIGURES '1-6;

FIGURES 20-26 disclose a modified construction wherein three sets of pairs of concentric inner and outer working chambers are provided, wherein:

FIGURE 20 is an end elevational view, parts of the fluid supply and exhaust conduits being broken away;

FIGURE 21 is an enlarged vertical longitudinal section taken substantially upon the plane indicated by the section line 2121 of FIGURE FIGURE 22 is a transverse vertical sectional view taken substantially upon the plane indicated by the section line 22-22 of FIGURE 21 and showing an outer or auxiliary set of inner and outer Working chambers;

FIGURE 23 is a transverse vertical sectional view taken substantially upon the plane indicated by the section line 2323 of FIGURE 21 and showing the main or intermediate set of inner and outer working chambers;

FIGURE 23A is a detail view taken substantially upon the plane of the section line 23A23A of FIGURE 23 FIGURE 24 is a group perspective view of a combined rotor constituting the rotary pistons for the main and the two auxiliary sets of working chambers;

FIGURE 24A is a group perspective view of the connector bodies by which the rings are pivotally connected and slidably mounted on their respective blades;

FIGURE 25 is a perspective view of a control valve for bypassing the intakes and exhausts of the three sets of Working chambers when the device is to run idle without load;

FIGURE 26 is a fragmentary perspective view of a portion of the apparatus showing the conduit and outoff valve assembly for the inlet and exhaust of fluid;

FIGURES 27-34 disclose a third embodiment of the invention wherein two sets of pairs of concentric inner and outer working chambers are provided, crank mechanism connected to the rotor and stator preventing oscillation of the rotor during its rotation, and wherein:

' FIGURE 27 is an end elevation with parts of the fluid conduits broken away;

FIGURE 28 is an enlarged vertical central longitudinal sectional View taken substantially upon the plane of the section line 2828 of FIGURE 27, parts being shown in elevation;

FIGURE 29 is a vertical transverse sectional View through the auxiliary working chambers taken substantially on the plane of the section line 2929 of FIGURE 28;

FIGURE 30 is a perspective view of the stationary abutment or blade of the auxiliary working chambers;

FIGURE 31 is a vertical transverse sectional view through the crank mechanism, taken substantially on the plane of the section line 31-'31 of FIGURE 28;

FIGURE 32 is a perspective view of one of the crank elements;

FIGURE 33 is a vertical longitudinal sectional view through the apparatus taken substantially upon the plane indicated by the broken section line 3333 of FIGURE 31; and

FIGURE 34 is a group perspective view of the components of the rotor.

When employed as a fluid motor or pump, all forms of the device herein set forth are inherently capable of reverse rotation or operation by merely reversing, in any suitable manner, the fluid inlet and exhaust conduit connections. Further, each embodiment may be interchangeably operated as a pump or motor by applying power to or taking it from the shaft.

Embodiment of Figures 1-6 Reference is now made specifically to the embodiment of FIGURES 1-6 which illustrates a preferred manner in which the basic principles of this invention may be applied. Illustrated therein is an expansible chamber device such as a fluid pressure pump or motor and which consists of a stator 10 having rotors 12 therein comprising rotary pistons. As shown, the stator may conveniently comprise a plurality of cylindrical, ring-like casings or housings which are designated by the numerals 14 and 16 in the embodiment illustrated. It will be understood that more than two units may be employed if desired, but preferably there are provided pairs of units,

1.- whose casings are secured together as by fastening bolts 18.

The opposite forward and rearward ends of the units 14 and 16 are provided with integral end walls 20*, having an outwardly projecting hub 21 and 22 and suitable bearing assemblies such as 24 and 26 in the forward end wall 20, and 28 in the rearward end wall 22 are recessed and housed therein for journaling a shaft 30 which extends centrally or axially of the stator 10. Any suitable lubricating system for the various hearing assemblies of this apparatus may be provided, as desired, but since the invention disclosed and claimed herein is not limited thereto, a disclosure thereof is omitted as superfluous.

The shaft 30 is splined as at 32 and has secured thereon eccentrics 52 upon which are mounted the rotors or rotary pistons 12. As seen best in FIGURES 2 and 3, a pair of cylindrical drums or cores 36 are fixedly secured to the sleeves 34 and are received within the rotors 12.

Each rotor, see FIGURES 5 and 3 especially, consists of a cylindrical ring 38 supported by an integral plate 40 at one side thereof, the other side being open and having secured thereto as by fastening bolts 42 a removable end wall or plate 44. It will now be understood that the rotor consists of anannular ring which vis U-shaped in cross section, the two supporting plates 40 and 44 which constitute the side members thereof embracing the central core 36 and having a sliding and fluid tight sealing engagement therewith. Since the invention claimed herein does not depend upon any particular sealing means between the rotor, the stator or the core, an illustration of the same has been omitted from the drawings and description in the interest of simplicity.

At their centers, the rotor supporting plates 40- and 44 are provided with cylindrical recesses or bores 46 in which are received bearing assemblies 48 and 50* which embrace eccentrics 52 carried by the shaft 30.

As will be best apparent from FIGURE 3, the eccentrics 52 for the rotor in the unit 14 are disposed at 180 to the eccentrics for the unit 16, in order to produce an opposed thrust for the two units whereby the pair of units will have a balanced torque with respect to the shaft 30 and whereby they will be counterbalanced as to oil. center weight.

As shown best in FIGURES 2 and 5, the ring 38 of the rotor is provided with a radially extending slot 6t) therethrough, while the cylindrical inner surface of each of the units 14 and 16 is provided with a radially disposed slot 62 which is radially aligned with the center of the slot 60.

Slidably received in the aligned slots and 62 is a blade 70, shown in FIGURES l, 2 and 6. This blade constituting a partition or abutment for the working chambers of the device is a body having a laterally enlarged upper end portion 72 together with a main or stem portion 74. A bore 76 extends centrally through the body to prevent a dashpot effect during the reciprocation of the blade in its slots, the stem being disposed and slidingly received in the slot 60 of the rotor 12 and being similarly disposed in a radially extending slot 78 in the core 36 of the stator. vAs the shaft 30 rotates, the eccentrics 52 splined thereto likewise rotate causing rotor 38 to oscillate around the shaft 30. Blade being pivotally connected through the pins 86 to the rotor 38 is thereby caused to reciprocate.

From FIGURE 1 it will be seen that the lateral portions 72 of the blade overlie the outer peripheries of the rotor 38. In their lower, arcuate surfaces, the lateral portions have slots 73 receiving packing or sealing elements 75 projecting therebeneath to thereby establish sealing engagement between the blade and arcuate recessed surfaces 81 on the ring. Channels and passages 77 and 79 permit the pressure to react on the top of the sealing elements 75 thereby forcing the latter down on the surfaces of the support plates 40 and 44, assuring an effectual seal therewith.

The core 36 is provided with a flat recessed surface 80 and a pair of guide members 82 are each secured to the surface 811 as by fasteners 84 upon opposite sides of the slot '78 to provide an extension guiding surface registering with the slot 78. Projecting laterally from opposite sides of the stem or main body portion 74 of the blade are a pair of pivot pins 86 accommodated by bores 87 in the blade 70, see in particular FIGURE 1, which are journaled in corresponding bores $8 in the support plates 40 and 44 of the rotor assembly. Thus, the ring 38 of the rotor is pivotally connected to the blade 70 for movement radially in the stator and oscillating about the core upon reciprocation of the blade, and for a pivotal swinging movement upon the blade as the rotor oscillates throughout the two working chambers as set forth here inafter.

A pair of sealing strips 90, see FIGURE 2, are received in recesses 92 on the surface 80 of the stator core 36 and have a sliding sealing engagement with the inner cylindrical periphery of the rotor ring 38 adjacent the opposite sides of the slot 60. A pair of similar sealing strips 94 received in corresponding channels or slots 96 provided on opposite sides of the blade 70 upon the inner cylindrical periphery of the stator housings 14 and 16 are adapted to have a sliding sealing engagement with the exterior cylindrical surface of the rotor ring 38. These sets of sealing elements are understood to be employed with each of the other embodiments, but are omitted from the drawings for simplicity of illustration.

Fluid inlet and outlet conduits 98 and 100 are secured to the stator casings as by fastening members 102 and register with fluid inlet and outlet ports 104 and 106,

respectively, which communicate thus with the annular chamber defined between the exterior cylindrical surface of the stator core 36 and the interior cylindrical surface of the stator casings 14 and 16.

The rotary piston or ring 38 is disposed and oscillates continuously in this annular chamber, being tangent to and engaging both the outer and inner walls thereof. It will be observed that there is thereby defined an outer working chamber designated by the letter A lying between the interior cylindrical surface of the casing sections 14 and 16 and the exterior cylindrical surface of the rotor ring 38; and an inner working chamber B lying between the interior cylindrical surface of the rotor ring 38 and the exterior cylindrical surface of the stator core' 36. As the ring oscillates in tangency with the stator and core, the outer and inner working chambers vary in volume, as shown in FIGURES 7-14 whereby to perform the various phases of the operation of the device as set forth hereinafter.

Referring next specifically to FIGURE 3 it will be seen that there is provided an annulus 110 which is seated and clamped in a suitable channel or annular groove 112 on the adjacent edges of the mating casing sections 14 and 16 to thus separate the two units of the apparatus. This partition plate 110 extends radially inwardly between the two supporting plates 44 and thus defines one wall of each of the two working chambers A of the two units, While the other end Wall thereof is defined by the end walls and 22.

Any fluid which may leak by the engagement of the rotor ring 38 and plate 44 with the side wall 22, or the cores 36, will accumulate in the recess 111 and will be delivered by the axial bore 112 extending in the shaft 30, and a cross bore 114 to the space surrounding the left end of the shaft. As shown in FIGURE 4, in conjunction with FIGURE 3, it will be seen that this accumulation of fluid is educted by the gear pump assembly including a driving gear 116 threadedly secured upon 'the shaft 31) and also constituting a lock nut for the rotor bearing assembly 48 and which drives a gear 118 journaled on a pin 120 carried by the end,wall 20. The

gear 113 in turn meshes with an idler gear 122 of the pump and which is journaled upon a pin 124 likewise carried by this end wall. The three gears 116, 118 and 122 are disposed in a recess 126 provided in the wall 20 and providing a gear chamber, this recess being provided with a closure plate 128. The fluid discharged by the cross passage 114 is permitted to enter the gear chamber and will be discharged by the gear through an exhaust port 131 and from thence may be educted as by a conduit fitting 132 to the exterior of the stator casing to any suitable designation. The gear pump thus serves to remove any accumulation of fluid leaking by the sealing means of the rotor.

It is to be noted that the above described leakage removal systems may be employed in the other embodiments disclosed herein but have been omitted from the drawings in order to simplify the showing.

Operation FIGURES 7-14 are sequential views diagrammatically illustrating at 45 intervals the rotation of the rotary piston 38 about the core 36 to thus effect the cyclic expansion and contraction of the outer and inner working chambers of each unit. This geometry of movement, with the ring remaining tangent on its outer and inner surfaces with the interior wall of the stator and the exterior wall of the core is identical for all embodimerits disclosed herein. It will be understood that this operation is identical in each unit, and regardless of whether the device functions as a pump or motor. In all views the blade 70, at the 0 position constitutes one end wall of each working chamber A and B.

In FIGURE 7 the longitudinal axis C of the eccentric 52 is shown at its top vertical position or at 0". The tangency of the top of the ring 38 with the stator casing 10 thus forms the outer chamber A extending substantially entirely from one side of the blade to the other. The tangency of the bottom of the ring with the core 36 defines the inner chamber B which is two sections, each extending from the point of tangency to opposite sides of the blade.

In the successive 45 intervals of rotation of the ring it will be seen that the working chambers A and B cyclically vary in volume, the shaded portions representing the charging or loading of the chambers by fluid through the intake 98 and the unshaded portions designating the exhausting of fluid from the two chambers: -A and B or their sections, through the exhaust 190. In the figures, the shaded portions represent the working chambers or sections thereof which are receiving a charge of fluid, while the unshaded portions designate those which are exhausting.

The operation of the embodiment of FIGURES 1-6 as a pump, in each unit of the device, is illustrated diagrammatically in the sequential views of FIGURES 15-19.

In all of the figures, as shown by the arrows, it is assumed that fluid is entering the pump or fluid motor through port 10 4 and is being discharged or exhausted through the port 106. This flow would be reversed, however, when the rotor is running in a reverse direction.

FIGURE 15 corresponding to FIGURE 11, shows the right side of the outer chamber A intaking while the left side thereof is exhausting; both the inlet and exhaust of the inner chamber B being closed momentarily by the engagement of the inside surfaces of the ring 38, on opposite sides of the slot 60, with the two sealing elements 9%.

Upon clockwise rotation of the ning from the position of FIGURE 15 to that of FIGURE 16, it will be seen that right hand portion of chamber A has enlarged and thus continues to take in fluid, while the left hand portion of chamber A has contracted, thereby exhausting fluid. However, the intake from port 104 through the slot 60 of the ring 3 8 into chamber B is still cut-off by the continued engagement of the sealing element at the right of the blade, while the sealing element at the left of the blade 70 has now opened and chamber B has begun its discharge of fluid.

At the succeeding position of FIGURE 17, exhausting of the left portion of chamber A has ceased by the closing of the exhaust port 106 by the passage of the ring 3 8 thereacross, and the right hand portion of chamber A has expanded to its maximum volume and its intake is about to terminate by engagement of the ring 3 8 with the sealing element 94 at the right of blade 70. The intake port of chamber B has opened and the right side portion is now being charged while the left side portion is on its exhaust stroke.

When the ring reaches the position of FIGURE 18, the intake of the outer chamber A has closed, its exhaust port has opened and the entire chamber A is now beginning its exhaust stroke. The inner chamber B is continuing to intake in its right hand portion and to exhaust in its left hand portion.

In the next phase shown in FIGURE 19, the right hand portion of outer chamber A is in its intake stroke while the left hand portion is exhausting. The exhaust port of chamber B has closed and the intake port is about to close 'with chamber B being at its maximum volume. From this position, the rotor moves to that of FIGURE 15 restarting the cycle of operation.

From the foregoing it will be now apparent that each chamber produces a very long duration working stroke and that both chambers, representing substantially the entire volume of the annular chamber between the stator and its core, except for that occupied by the blade, is effective as a working volume. The relatively slight pulsations produced by the overlapping of the separate intakes and discharges of the working chambers A and B are balanced by the 180 phase relation of those of the second or opposed unit.

In this, as in the following embodiments, each of the working chambers is sealed against escape of the fluid whereby the accuracy of flow and the working efiiciency of a positive displacement of fluid are realized. In addition, the reversal of inertias and thrusts of reciprocating pants are substantially replaced by the mechanically more desirable continuous and uniform rotation of the rotary piston, thereby securing less wear, reducing strains upon the structure and obtaining a longer useful life for the apparatus.

Embodiment of FIGURES 20-26 The embodiment of the apparatus illustrated in FIG- URES 20-26, operating upon the same general principles as those of the embodiment of FIGURES 16, provides an apparatus having a centrally disposed set of inner and outer working chambers together with auxiliary sets of inner and outer working chambers positioned on opposite sides of the central set, together with modified rotor and stator structure.

Referring first to FIGURES 20 and 21, it will be seen that a generally cylindrical and drum-like stator 150 consists of two or more annular housings or casings divided transversely of the stator to provide aligned registering sections 152 and 1154. These sections are coupled together as by fastening bolts 156, it being observed that these sections have integral end walls 158 and 160, the former being provided with a central axially extending hub 162 while the latter has an axially positioned cover plate 164 detach-ably mounted thereon as by fastening bolt-s 166.

The hub 16 2 is provided 'with suitable bearing asse blies 168 and 170, while the end wall 160 is in turn provided with an axial opening therethrough as at 172 for the reception of a bearing assembly 174, access to which is obtained by removing the cover plate 164. These bearing assemblies rotatably mount a shaft 176 by which power is supplied to or taken from the rotor of the device as set forth hereinafter. As in the preceding embodiment '8 the shaft 176 is provided with splines 178 by means of which there are secured thereto a pair of eccentrics 180 together with a core 182.

-It should be noted, at this point, that in some instances, in all of the embodiments illustrated, the core 182 instead of being splined to the shaft 176 for rotation therewith, may be journaled upon the shaft for free rotation thereon.

Mounted upon the two eccentrics 180 are bearing assemblies 184 by means of which a rotor assembly is journaled upon the shaft for rotation about an axis which is eccentric thereto.

As will be more readily apparent, from a comparison of FIGURES 21, 22 and 2.3, the interior of the stator is hollow, providing a chamber whose circumferential walls are cylindrical and are concentric with the axis of the shaft 176, these walls providing three longitudinally spaced annular working chambers in which the components of the rotor assembly are disposed for operation.

Referring now particularly to FIGURES 24 and 21, it will be observed that the rotor assembly consists of a pair of components which are detachably secured together. Thus, the rotor includes as its major component a circular support plate having a cylindrical hub portion 19-2 journaled upon one of the bearing assemblies 184 carried by an eccentric 180, together with oppositely and laterally projecting C-sh-aped rings 1'94 and 196. The ring 1 94 is operably disposed in an outer or auxiliary working chamber 198 in the stator section 152, see FIG- URE 2.1, and constitutes a rotary piston in said chamber, while the ring 1 96 is disposed in the main or central working chamber 200 and comprises the rotary piston element for the latter.

It will be further observed from FIGURE 21 that the inner flat annular surface of the support plate 190 at its inner periphery bears against and overlies the side of the core 182 to establish a sliding and sealing engagement therewith in the same manner set forth in connection with the corresponding engagement of the rotor support plates with the core of the preceding embodiment.

The other or minor component of the rotor assembly likewise comprises a circular support plate 202 having a cylindrical hub or bearing surface 204 by which it is journaled upon the bearing assembly 184 of the other eccentric 180 as shown in FIGURE 21, and projecting laterally from this support plate is a C-shaped ring 206 similar to the ring 194 and constituting a rotary piston which is disposed in the other auxiliary working chamber 208. The ring 206 is provided with a plurality of bores 210 and fasteners 212 extend through these bores and into registering bores 214 in the ring 196 for securing the two sections of the rotor assembly in their assembled relation. In this assembled relation it will be observed that the support plate 202 also embraces and has a fluid tight sealing and sliding engagement with the side of the core 182.

Examining now FIGURE 21 more closely, it will be observed that the hollow interior of the stator is appropriately contoured to provide annular chambers 198, 200 and 208 which constitute the sets of annular working chambers of the device, and also further annular chambers 220 and 222 disposed between the above mentioned annular working chambers and which serve to receive and house the radially projecting peripheries of the support plates 190 and 202.

It will be observed that owing to the eccentric mounting of the rotor and therefore the radially enlarged path of travel of the plates 190 and 202, the chambers 220 and 222 are necessarily large enough to accommodate the same.

It will be observed that a pair of lock nuts 224 are threaded upon the shaft 176 for securing the rotor components, the core and the associated bearing assemblies in proper relation.

As in the preceding embodiment, any desired and suitable sealing means may be provided between the relatively moving parts of the rotor and stator assembly, but

since the invention claimed herein is not restricted to any particular type of sealing means and since such sealing means are in themselves well known in the art, illustration of the same has been omitted in order to simplify the showing in the drawings.

However, as in the preceding embodiment, there are provided at the opposite sides of the rotor assembly, in the end walls 153 and 16d of the stator, a pair of collection chambers 226 and 228 whereby any fluid leaking past the sealing means between the rotor and stator will accumulate, and the shaft is provided with an axial bore 23h communicating with cross bores 232 and 234 registering with these two collection chambers whereby the fluid may be educted from the stator by a suitable pump, not shown, as for example in the same manner as that set forth in connection with the preceding embodiment.

Referring now to FIGURES 2l23, it will be seen that each of the annular working chambers is provided with a partition or blade extending entirely thereacross. Thus, the central or main annular working chamber has a blade 24% which has its upper end received in a slot M2 formed in the cylindrical ring insert 155 press fitted into the stator section 154, a suitable key 244 serving to rigidly secure this blade in position. The lower end of this blade engages the core 132, and if desired may extend into a slot in the same, if the core is not fixedly secured to the shaft 176. Where the core is however splined to the shaft 176 as suggested in FIGURE 23, the end of the blade 24% has merely a rubbing or sliding contact with the periphery of the core.

Each of the auxiliary annular chambers 198 and 293 is likewise provided with an auxiliary blade 246 having its upper end secured in a slot 243 in the stator, in rigid position as by a spline or key 250. Since the structure of the auxiliary blades is identical with that of the main blade, a further description of the mounting of the same is believed to be unnecessary.

In this embodiment, in view of the stationary mounting of the blades, it is necessary for the rings or rotary pistons to have a pivotal and sliding connection with the blades. For this purpose, as shown in FIGURES 22 and 23, a connector block 260 is provided having a slot 262 which slidably embraces the main blade 240, while a similar connector block 264 with slot 266 slidably embraces each of the auxiliary blades 240. The connector blocks are thus freely slidable radially along their blades.

The connector blocks are received between the slotted ends of the C-rings or rotary pistons I94, 1% and 206. The ends of the C-rings are pivotally attached to these connector blocks by means of pivot pins 268 and 270, the former being retained in semi-cylindrical grooves 272 provided in one edge of each of the C-rings and in corresponding complementary cylindrical grooves 2'74 provided in the opposed edge or face of the connector bodies 260 and 264. Thus, the pivot pins 253 are employed to retain the adjacent portions of the -ring and the connector body in a constant but pivotal relation. The other pivot pins 27d are likewise secured to the semicircular grooves 276 at the opposite side of the connector bodies 2% and 264, and are pivotally and slidably received in the semi-cylindrical grooves 278 formed in the ends of the C-rings 194, 196 and 206 at the other side of the slotted ends of these rings.

As shown in FIGURE'23A, each of the pivot pins 276 has a flange 2711. which extends beyond one end of the pin and has an arm 273 projecting therefrom. The arm 273 is guidingly and slidably received in a slot 275 disposed in the side of the ring andextending between the open end of the ring and the slots 302, 306 referred to hereinafter. This connection permits the associated end of the rings to move slightly towards and from their connector bodies and their blades as well as to pivot upon them. Thus, the C-rings are movable with those blocks upwardly or downwardly upon the blades 24!) and 24-6 for a purpose to be set forth hereinafter.

Adjacent their pivotal connection with the connector bodies 260 and 264, each of the C-rings is provided with a pair of slots for the passage of fluid through the rings during the charging and exhausting of the inner working chamber lying upon the inside of each ring.

Thus, the ring or rotary piston of the main annular working chamber is provided with a pair of slots or ports 300 and 3132 extending therethrough as shown in FIGURES 24 and 23, while each of the auxiliary rings or rotary pistons is provided with corresponding ports 3594 and 3%. It will be observed that each ring thus has a port disposed on opposite sides of its blade.

The stator is provided with a plurality of inlet conduits as at 308, 310 and 312 which respectively communicate with corresponding ports in the stator opening into the annular working chambers, such as the port 314 communicating with a conduit 312 and the port 316 communicating with a conduit 398. These three conduits in turn are connected to a header 318 by which fluid may be supplied to each of the annular working chambers. Manual control valves indicated at 3220 en able the supply of fluid for any selected conduit to be cut-off when desired.

There is also provided a second series of conduits 322., 324 and 326 cooperating with the conduits 368, 310 and 312, respectively, as will be apparent from FIGURES 20 and 26. As will be observed from FIGURE 22, the conduit 326 communicates with a port 328, while as shown in FIGURE 23, the conduit 322 communicates with a port 33%. Manual control valves 329 are of course provided for each of these last mentioned conduits, and a header 332 is likewise connected thereto. By means of the headers fluid may thus be supplied to and exhausted from all of the annular working chambers of the apparatus.

As will be readily understood, the rotors may turn in either direction, it being merely necessary to reverse the supply of fluid to and the exhaust of fluid from the head ers 318 and 332. In addition, any selected annular working chamber may have its fluid supply cut-01f by properly manipulating the manual control valves 32%.

In some instances, it may be desirable for one or all of the annular working chambers to be rendered inoperative and to run idle without load, as for example where the apparatus is employed as a fluid motor in an automotive vehicle and it is desired to free wheel the same. For this purpose there is provided a bypass passage assembly for connecting any selected annular working chamber across its blade. Thus, the main annular working chamber may be provided with a pair of bypass passages 340 and 342 respectively communicating with the ports 316, 33% and with a valve bore 344 extending longitudinally of the stator, while each of the auxiliary annular working chamhers is likewise provided with bypass passages 346, 348, each communicating with its corresponding ports on opposite sides of the blade 246, and communicating with the above mentioned longitudinally extending valve passage or bore 344.

A single control valve in the form of a cylinder 359, see FIGURE 25, is rotatably received in the bore 344, being provided with a manual handle 352.. The valve is provided with valve recesses 354, 356 and 358, the recess 354 as shown in FIGURE 21 being operable to connect the intake and exhaust ports 316 and 330 of the main annular working chamber, whereby to prevent any load being applied to the rotor of that chamber. Similarly, the valve recess 356 is adapted to control the annular working chamber of the auxiliary rotary piston 194, this being the chamber 198; while the recess 358 in turn controls the annular Working chamber 2&8 of the rotary piston 2%.

Referring now more particularly to FIGURES 22 and 23 it will be seen that each of the rotary pistons operating in its annular working chamber divides the latter into outer working chambers A and inner working chambers B. The epicyclic travel of each piston in its annular Working chamber, so that the piston is at all times tangent to the stator at the 'outer periphery of the piston and is always tangent to the core at the inner periphery of the piston is identical with the operation discussed in detail and illustrated in connection with the preceding embodiment and diagrammatically represented in FIGURES 7-19 thereof.

As in the preceding embodiment, sealing elements may be provided between the ring or rotary pistons and the cooperating adjacent surfaces of the core and of the stator, in the same manner set forth in the preceding embodiment in connection with the sealing elements 9% and 94. In order to simplify the illustration in the drawings, and avoid duplication of showing and explanation, it has been deemed unnecessary to repeat this showing and description in connection with the present embodiment.

Embodiment FIGURES 27-34 In the embodiment illustrated in FIGURES 27-34, there is disclosed a two unit construction consisting of a main annular working chamber having inner and outer working chambers together with an auxiliary chamber having auxiliary inner and outer working chambers and wherein a modified rotary piston or ring is employed having a crank mechanism for preventing oscillation of the ring during its rotation.

Referring first to FIGURES 28 and 33 it will be seen that the apparatus in accordance with this embodiment consists of a stator 364) which may comprise a pair of casing sections 362 and 35 which are retained in assembled relation as by fastening bolts 366 extending therethrough. The two casing sections include integral end walls 368 and 370, the former having an axial forwardly projecting tubular sleeve or hub 372 while the latter is provided with a central opening 374 which is closed by a removable closure plate 376 secured as by fastening means 378.

Received in the hub 372 are a paig of spaced bearing assemblies 380 and 332, while the opening 374 in the end wall 370 has a bearing assembly 384 therein. These three bearing assemblies rotatably support a centrally disposed shaft 386 by which power is supplied to or taken off from the rotor assembly to be hereinafter described.

As in the immediately preceding embodiment, the shaft is preferably splined as at 388 and eccentrics 390 are thereby fixedly secured to the shaft. Bearing assemblies 392 are mounted upon these eccentrics and support the rotor assembly as set forth hereinafter, while a drum shaped core 394 is disposed between the eccentrics and carried by the shaft.

As in the preceding embodiment, the core may be either fixedly secured to the splines of the shaft or may be freely rotatable upon the shaft, since the principles of this invention are not limited to either mounting of the core upon the shaft.

Referring next to FIGURES 33 and 34 it will be observed that the rotor assembly consists of two component sections, the major section comprising a circular support plate 395 from which laterally projects a C- shaped ring 396 comprising a rotary piston. The other section likewise includes a circular support plate 398 together with a C-shapedring or rotary piston 400. Aligned internally threaded apertures or bores 402 and 404 receive the fastening bolts 406 by Which the two sections of the rotor are fixedly secured together. As shown in FIG- URE 33, these two sections when clamped together have their support plates 395 and 3% slidably embracing the core 394 for a fluid tight sealing engagement therewith. As in the preceding embodiments, any suitable sealing elements may be provided between the rotor and the stator components, in order to prevent the leakage of fluid pressure therebetween, but inasmuch as the invention claimed herein does not depend upon nor require any specific sealing means, and since such sealing means are well known in the art, a detailed description illustrating the same has been omitted as being unnecessary to an understanding of the invention claimed.

The rotor support plates 395 and 39 8 have bores 468 and 410 which receive the above mentioned bearings 392 by which the support plates are mounted upon the eccentric members.

As in the preceding embodiments, the stator members have fluid collection chambers 412 and 414 whereby any fluid leaking between the rotor and stator components may be collected, and the shaft 386 is provided with an axial bore 416 together with a cross bore 418, whereby the two collection chambers are placed in communication with each other. In this particular embodiment of the invention, means are provided which prevent oscillation of the rotor assembly during the rotary travel of the latter throughout the working chambers of the device. For this purpose, there are provided a plurality of cranks operatively connecting the stator and the rotor. As shown in FIGURES 32 and 33, the cranks include crank discs 42%) having oppositely disposed and oppositely extending crank throws 422 and 424. As will be best apparent from FIG- URE 33, the end wall 368 is provided with recesses 425 for receiving the crank discs 420, and with bores 42%; carrying bearing assemblies 430 by which the crank throws 422 are rotatably carried by and journaled in the end wall 368. In a similar manner the rotor support plate 395 is provided with recesses 432 receiving bearing assemblies 434 by which the other crank throw 424 is rotatably journaled in and secured to the rotor assembly.

As shown in FIGURE 31, four such crank assemblies are provided, although any desired number may be employed. It will be observed from FIGURE 31 that as the eccentrics rotate, they in turn cause a rotary travel of the rotor assembly, while the crank elements will permit such rotary travel but will prevent oscillation of the rotor during such rotation. The arrangement is such that an epicyclic movement is imparted to the rotor, whereby the rotary pistons 396 and 400 thereof move about the annular working chamber provided between the stator and the core, with the outer surface of the rotary piston in constant tangency with the stator, and with the inner surface of the rotary piston in constant tangency with the core.

Inasmuch as the operation of the rotary pistons in their annular working chambers is identical with that set forth hereinbefore, in connection with the other embodiments, and particularly in connection with the diagrammatic views of FIGURES 7-l9, a detailed explanation of the same appears to be unnecessary.

Refer-ring again to FIGURE 33 it will be seen that the stator is provided with annular working chambers 440 provided in the stator ring 441 and 442 in which are received the rotary pistons 396 and 400 respectively. There are also provided annular chambers 444 and 446 which respectively provide clearance for and receive the support plates 395 and 398 of the rotor assembly.

lAs in the preceding embodiments, each of the annular working chambers is provided with an outer working chamber A and an inner working chamber B, these chambers lying on opposite sides of the rotary piston lying within the annular working chambers.

As shown in FIGURE 34, the rotary pistons or C-rings are provided with open slots 448 and 450 and a pair of blades or partitions 452 and 454 are provided, the former being received in a slot 456 in the stator, while the latter is received in a slot 458 therein, these blades projecting across the annular working chambers 440 and 4-42 respectively and within the slots 448 and 450. Each of these blades is provided with a transversely disposed channel 460 for the reception of a transversely extending key 462 by which the blades are retained in place.

It will be understood that in this form of the invention suitable sealing elements such as those indicated at 9% and 94 in the embodiment of FIGURES 1-6 may be provided for establishing a sealing engagement between the inner and outer surfaces of the rotary piston and the adjacent surfaces of the core 394 and the stator. I

In this form of the invention the rotary pistons are given a rotary movement throughout their chambers, but remain parallel in all of their positions by virtue of the operation of the crank members previously described. Thus, any oscillation of the rotary pistons is prevented.

It will be understood that the operation of the pistons in their working chambers is similar to that set forth in connection with the preceding embodiments and as described in detail in connection with FIGURES l6, in the diagrammatic views of FIGURES 7-19, and accordingly a further description of the same is deemed to be unnecessary.

A pair of conduits 470, 472 are disposed on one side of the blades, while corresponding conduits 474 and 476 are disposed upon, the opposite side thereof, as will be apparent from FIGURE 27. The conduits 472 and 476 communicate respectively with ports 478 and 480 communicating with the annular working chamber 442, while the conduits 470 and 474 similarly communicate with these chambers.

The operation of the rotary pistons in their working chambers is similar to that previously set forth and a further description of the same is believed to be unnecessary. It will be understood, however, that the control valves for the individual conduits, and the bypass valve arrangement described hereinbefore may be employed with this embodiment also if desired.

In this embodiment, a slightly modified construction is provided for driving the gear pump by which the collection of fluid accumulating in the chambers 412 and 414 may be removed. As shown in FIGURES 31 and 33, one of the crankshafts 420 is provided upon its periphery with a driving gear 490* which in turn meshes with a pump gear 492 journaled upon an idler shaft 494, this last mentioned gear in turn meshing with a further pump gear 496 journaled upon a shaft 498. As in the preceding embodiments, the shafts of the pump gears are carried by the end wall 368.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes 'will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. An expansible chamber device including a stator having a central opening and a rotor received therein,

(a) said stator having a peripheral wall and a pair of end walls secured thereto and enclosing said central opening,

(b) an annular projection on said peripheral wall extending into said opening and having a cylindrical internal surface together with planar side surfaces,

() said side surfaces together with the adjacent surfaces of said end walls and said peripheral wall defining annular recesses on opposite sides of said cylindrical internal surface,

(d) a cylindrical core disposed in said opening and having a cylindrical exterior surface centrally of said cylindrical internal surface and defining therewith a main annular chamber,

(e) said stator having an auxiliary annular chamber therein in spaced coaxial relation to said main chamber and provided with inner and outer cylindrical surfaces,

( said rotor consisting of a pair of support plates each received in one of said annular recesses and slidably engaging the side walls of the latter,

(g) a ring in said annular chamber comprising a main piston and being secured to and extending between said support plates and surrounding said core and defining with said cylindrical surfaces inner and outer Working chambers in said main chamber,

(h) an auxiliary ring secured to one of said support plates and projecting laterally therefrom into said auxiliary chamber and comprising an auxiliary piston defining inner and outer auxiliary working chambers,

(i) each of said rings having a transverse slot therethrough,

(j) each of said main and auxiliary working chambers having a blade therein extending through and slidable in the associated slot and providing a stationary piston in both of the associated inner and outer Working chambers,

(k) fluid intake and exhaust means communicating with each of said working chambers,

(1) means causing epicyclic movement of said rings throughout said annular chambers with the rings each being in tangency with both of said cylindrical surfaces of an annular chamber.

2. The combination of claim 1 including an eccentric upon which each of said support plates is journaled.

3. The combination of claim 1 wherein said stator consists of a pair of complementary axially abutting sections, each section including a portion of said peripheral wall and one of said end walls, said annular projection comprising a member clampingly embraced and retained between said section-s.

4. The combination of claim 1 wherein said ring projects laterally from one of said support plates, the other support plate being detachably secured to said ring.

5. The combination of claim 1 including means for separately collecting fluid leaking to opposite sides of said rotor, means for combining the collected fluid in one collection chamber, a pump disposed in said collection chamber for educting collected fluid therefrom.

6. The combination of claim 1 including means for separately collecting fluid leaking to opposite sides of said rotor, means for combining the collected fluid in one collection chamber, a pump disposed in said collection chamber for educting collected fluid therefrom, said pump including a pair of idler gears rotatably supported upon a wall of said collection chamber, a driving gear meshed with one of said idler gears, said driving gear being operatively connected to said support means.

7. The combination of claim 1 including means for separately collecting fluid leaking to opposite sides of said rotor, means for combining the collected fluid in one collection chamber, a pump disposed in said collection chamber for educting collected fluid therefrom, said pump including a pair of idler gears rotatably supported upon a Wall of said collection chamber, a driving gear meshed with one of said idler gears, said driving gear being operatively connected to said support means, said driving gear being operatively connected to said stator and to said support means.

8. An expansible chamber device comprising a stator and a rotor therein, said stator having a plurality of annular working chambers disposed in axially spaced sideby-side relation, each chamber including cylindrical inner and outer walls, said stator having annular recesses between each pair of adjacent annular chambers, said rotor including a pair of support plates each received in one of said recesses, rings carried by and projecting laterally from said support plates with one ring being received in each annular working chamber and extending from sideto-side thereof and cooperating with the cylindrical inner and outer walls, each of said rings having a transverse slot therethrough, each annular working chamber having a blade therein extending through and slidable in the associated slot and providing a stationary partition in both the inner and outer chambers of each annular working chamber, fluid intake and exhaust means communicating with each of said Working chambers whereby upon rota- 153 tion of said rings, fluid is taken into and discharged from said working chambers through said intake and exhaust means, respectively.

9. The combination of claim 8 wherein said working chambers comprise a centrally disposed main working chamber and an auxiliary working chamber on each side of the main chamber, said rings comprising a main piston connecting a pair of said support plates and a pair of auxiliary pistons each projecting laterally from a support plate.

10. The combination of claim 9 wherein each of said auxiliary pistons is integral with a support plate.

11. The combination of claim 10 wherein said main piston is detachably connected to at least one of said support plates.

12. An expansible chamber device comprising a stator, a plurality of annular working chambers disposed in said stator in spaced side by side relation and each including cylindrical outer and inner walls, a rotor including a pair of support plates, rings carried by said support plates and projecting laterally therefrom, each ring being received in an annular working chamber and extending from side to side thereof to constitute a rotary piston whereby to define concentric outer and inner chambers therein, each ring having a transverse slot and a blade in each annular working chamber extending through said slot to provide a partition in both said outer and inner chambers, means connecting said ring to said stator for maintaining said ring in parallel positions throughout its movement, intake means and exhaust means for each of said annular chambers.

13. The combination of claim 12 wherein said rotor includes a main ring disposed between said pair of support plates and disposed in a main annular Working chamber and at least one auxiliary ring carried by the outer side of one of said support plates and disposed in an auxiliary annular working chamber at one side of said main chamber.

14. The combination of claim 12 wherein each support plate has a ring carried by one side thereof, one of said support plates being detachably secured to the ring of the other support plate.

References Cited in the file of this patent UNITED STATES PATENTS 196,732 Winkler Oct. 30, 1877 385,832 Allyn July 10, 1888 724,056 Scott Mar. 31, 1903 1,229,676 Tice June 12, 1917 1,263,550 Gollings Apr. 23, 1918 1,271,729 Kristufek July 9, 1918 9 1,378,065 Varley May 17, 1921 1,378,088 Boyer May 17, 1921 1,456,461 Page May 22, 1923 1,489,416 Anderson et al Apr. 8, 1924 1,560,624 Varley Nov. 10, 1925 1,658,803 Heinrich Feb. 14, 1928 1,780,109 Berglund Oct. 28, 1930 1,974,225 Varley Sept. 18, 1934 2,073,101 Fox Mar. 9, 193 2,538,598 Stratveit Jan. 16, 1951 2,628,770 Bowering -2 Feb. 17, 1953 2,635,553 Gordinier Apr. 21, 1953 2,649,053 Stratveit Aug. 18, 1953 2,783,714 Stratveit Mar. 5, 1957 2,856,861 Adams et al Oct. 21, 1958 2,966,898 Rydberg Jan. 3, 1961 FOREIGN PATENTS 570,127 France Jan. 12, 1924 755,955 France Sept. 18, 1933 716,761 Germany Jan. 28, 1942 541,837 Great Britain Dec. 15, 1941 531,190 Italy July 22, 1955 10,739 Norway May 12, 1902 133,350 Sweden Oct. 25, 1951 

1. AN EXPANSIBLE CHAMBER DEVICE INCLUDING A STATOR HAVING A CENTRAL OPENING AND A ROTOR RECEIVED THEREIN, (A) SAID STATOR HAVING A PERIPHERAL WALL AND A PAIR OF END WALLS SECURED THERETO AND ENCLOSING SAID CENTRAL OPENING, (B) AN ANNULAR PROJECTION ON SAID PERIPHERAL WALL EXTENDING INTO SAID OPENING AND HAVING A CYLINDRICAL INTERNAL SURFACE TOGETHER WITH PLANAR SIDE SURFACES, (C) SAID SIDE SURFACES TOGETHER WITH THE ADJACENT SURFACES OF SAID END WALLS AND SAID PERIPHERAL WALL DEFINING ANNULAR RECESSES ON OPPOSITE SIDES OF SAID CYLINDRICAL INTERNAL SURFACE, (D) A CYLINDRICAL CORE DISPOSED IN SAID OPENING AND HAVING A CYLINDRICAL EXTERIOR SURFACE CENTRALLY OF SAID CYLINDRICAL INTERNAL SURFACE AND DEFINING THEREWITH A MAIN ANNULAR CHAMBER, (E) SAID STATOR HAVING AN AUXILIARY ANNULAR CHAMBER THEREIN IN SPACED COAXIAL RELATION TO SAID MAIN CHAMBER AND PROVIDED WITH INNER AND OUTER CYLINDRICAL SURFACES, EACH RECEIVED IN ONE OF SAID ANNULAR RECESSES AND (F) SAID ROTOR CONSISTING OF A PAIR OF SUPPORT PLATES SLIDABLY ENGAGING THE SIDE WALLS OF THE LATTER, (G) A RING IN SAID ANNULAR CHAMBER COMPRISING A MAIN PISTON AND BEING SECURED TO AND EXTENDING BETWEEN SAID SUPPORT PLATES AND SURROUNDING SAID CORE AND DEFINING WITH SAID CYLINDRICAL SURFACES INNER AND OUTER WORKING CHAMBERS IN SAID MAIN CHAMBER, (H) AN AUXILIARY RING SECURED TO ONE OF SAID SUPPORT PLATES AND PROJECTING LATERALLY THEREFROM INTO SAID AUXILIARY CHAMBER AND COMPRISING AN AUXILIARY PISTON DEFINING INNER AND OUTER AUXILIARY WORKING CHAMBERS, (I) EACH OF SAID RINGS HAVING A TRANSVERSE SLOT THERETHROUGH, (J) EACH OF SAID MAIN AND AUXILIARY WORKING CHAMBERS HAVING A BLADE THEREIN EXTENDING THROUGH AND SLIDABLE IN THE ASSOCIATED SLOT AND PROVIDING A STATIONARY PISTON IN BOTH OF THE ASSOCIATED INNER AND OUTER WORKING CHAMBERS, (K) FLUID INTAKE AND EXHAUST MEANS COMMUNICATING WITH EACH OF SAID WORKING CHAMBERS, (L) MEANS CAUSING EPICYCLIC MOVEMENT OF SAID RINGS THROUGHOUT SAID ANNULAR CHAMBERS WITH THE RINGS EACH BEING IN TANGENCY WITH BOTH OF SAID CYLINDRICAL SURFACES OF AN ANNULAR CHAMBER. 